powshell controls directory file permissions

for($file=[IO.File]::OpenText("C:\Users\Administrator\Desktop\user_list.txt") ; !($file.EndOfStream);$line=$file.ReadLine() )
{
$url="D:\ftpfile\$line";
$a=Test-Path $url;
if ($a){
cacls $url /T /E /g ${line}:r
}
}
$file.Close()